Source and nature of inhaled atmospheric dust from trace element analyses of human bronchial fluids.

Rapid volcanic eruptions quickly ejecting large amounts of dust provoke the accumulation of heavy metals in people living in surrounding areas. Analyses of bronchoalveolar lavage samples (BAL) collected from people exposed to the paroxysmal 2001 Etna eruption revealed a strong enrichment of many toxic heavy metals. Comparing the BAL to the dust composition of southeastern Sicily, we found that only V, Cr, Mn, Fe, Co, and U enrichment could be related to the volcanic event, whereas Ni, Cu, Cd, and Pb contents come from the dissolution of particles of anthropogenic origin. Furthermore, the nature of these inhaled anthropogenic particles was revealed by anomalous La and partially Ce concentrations in BAL that were consistent with a mixture of road dust and petroleum refinery emissions. Our results indicate that trace element distribution in BAL is a suitable tracer of human exposure to different sources of inhaled atmospheric particulates, allowing investigations into the origin of source materials inhaled by people subjected to atmospheric fallout.

Anti-inflammatory effects of pre-seasonal Th1-adjuvant vaccine to Parietaria judaica in asthmatics.

BACKGROUND: The ultra-short course pre-seasonal allergy vaccine, containing appropriate allergoids with the adjuvant monophosphoryl lipid A (MPL), may be effective in treating allergic symptoms. OBJECTIVE: To explore the timing of the immunological responses to the pre-seasonal allergy vaccine. METHODS: Four subcutaneous injections of the active product (Pollinex Quattro) were administered to 20 Parietaria-sensitive intermittent asthmatics (M/F: 12/8; age: 48 ± 10 years; FEV(1)% predicted: 108% ± 12%) during the 6 weeks prior to the start of the pollen season. Exhaled breath condensate (EBC) was collected immediately before the first and immediately after the last injections (t(1) and t(2)), during the pollen season (t(3)) and after (t(4)) the pollen season. EBC was analyzed to determine the levels of pH and 8-isoprostane. Ten Parietaria-sensitive asthmatics served as the untreated control group at t(1) and t(2). RESULTS: Measured pH levels were 7.64 ± 0.33 at t(1), 7.67 ± 0.23 at t(2), 7.72 ± 0.34 at t(3), and 7.82 ± 0.34 at t(4) (P = 0.049 vs baseline). 8-isoprostane levels were significantly lower than baseline at each visit (mean difference from baseline, for t(2): -0.77 pg, P = 0.031; for t(3): -0.92 pg, P = 0.010; for t(4): -0.70 pg, P = 0.048). In the control group, pH levels were 7.73 ± 0.26 at baseline and did not change after 6 weeks (7.79 ± 0.25, P = 0.33). Similarly, the concentrations of 8-isoprostane in the control group were not different from those of the study group at baseline (P = 0.86), and the levels remained unchanged after 6 weeks (P = 0.58). CONCLUSION: These findings show that the ultra-short course of vaccine adjuvated with MPL acutely reduces the degree of airway inflammation, as expressed by markers of oxidative stress, and suggest that this reduction is maintained during and after the pollen season.

Altered CD94/NKG2A and perforin expression reduce the cytotoxic activity in malignant pleural effusions.

CD94/NKG2A is an inhibitory receptor expressed by NK cells and cytotoxic lymphocytes and, upon activation by HLA-E, downregulates the cytolytic activities of these cells thus representing a tumour immune escape mechanism. This study was aimed at assessing whether cytotoxic lymphocytes (CD8+) and NK cells from malignant pleural effusions have a deregulated expression of CD94/NKG2A. The expression of membrane CD94/NKG2A and perforin was evaluated by flow-cytometry in CD8+ and NK cells from pleural effusions and autologous peripheral blood of cancer (n=19) and congestive heart failure (CHF) (n=11) patients. Intracellular CD94/NKG2A expression was evaluated by flow-cytometry in pleural effusion CD8+ and NK cells from cancer patients (n=10). Cytotoxic activity against cancer cells exerted by pleural and autologous peripheral blood T lymphocytes from cancer patients was assessed by flow-cytometry assay. Pleural CD8+ from cancer patients showed a reduced expression of membrane CD94/NKG2A and perforin when compared to autologous peripheral blood and CHF pleural effusions. Reduced numbers of NK cells were present in pleural effusions from both cancer and CHF patients. Pleural NK from cancer patients showed a reduced expression of membrane CD94/NKG2A and perforin when compared to autologous peripheral blood. Pleural T lymphocytes from cancer patients exhibited a reduced cytotoxic activity against cancer cells when compared to autologous peripheral blood T lymphocytes. The intracellular expression of CD94/NKG2A in CD8+ and NK cells from cancer patients was higher than membrane expression. In conclusion, this study provides compelling evidences of new mechanisms underlying the reduced host defence against cancer within the pleural space.

The effect of intranasal corticosteroids on asthma control and quality of life in allergic rhinitis with mild asthma.

BACKGROUND: The mechanisms through which rhinitis affects asthma have not been completely elucidated. We explored whether the effect of nasal treatment on asthma control and respiratory-related quality of life (HRQoL) is mediated by inflammatory changes of the upper and lower airways. METHODS: Allergic rhinitics with mild asthma were randomized to a 14-day treatment period with either nasal budesonide 100 µg, 1 puff per nostril twice a day, or placebo. Clinical, functional, and biological evaluations were performed before and after treatment. RESULTS: Twenty subjects (M/F: 10/10; age: 31 ± 15 years; mean ± SD) were enrolled, and a total of 17 individuals completely participated in the study. Lung function was within the normal range. The total asthma control test (ACT) score was 20 ± 5.3 and the RHINASTHMA Global Summary (GS) was 44 ± 15. The percentage proportion of eosinophils in nasal lavage was 9.9% and significantly correlated with spirometric parameters reflecting peripheral airway function (for FEF(50): r = 0.48, p = .03; for FEF(25): r = 0.47, p = .03). The pH of the exhaled breath condensate (EBC) was 7.33 ± 0.4. After nasal treatment, the percentage proportion of eosinophils fell significantly (p = .002), and changes in percentage proportion of eosinophils were associated with changes both in the ACT score (r = 0.76, p = .04) and in the RHINASTHMA GS (r = 0.77, p = .02). The increase in the pH of the EBC was not associated with changes in the ACT score or with the RHINASTHMA GS. CONCLUSIONS: These findings confirm that, in subjects with allergic rhinitis with mild asthma, nasal inflammation impacts on asthma control and HRQoL. The improved control of respiratory symptoms obtained with nasal corticosteroids seems to be mediated by functional changes in the peripheral airways.

Effects of exercise training on airway responsiveness and airway cells in healthy subjects.

Airway responsiveness to methacholine (Mch) in the absence of deep inspirations (DIs) is lower in athletes compared with sedentary individuals. In this prospective study, we tested the hypothesis that a training exercise program reduces the bronchoconstrictive effect of Mch. Ten healthy sedentary subjects (M/F: 3/7; mean + or - SD age: 22 + or - 3 yr) entered a 10-wk indoor rowing exercise program on rowing ergometer and underwent Mch bronchoprovocation in the absence of DIs at baseline, at weeks 5 and 10, as well as 4-6 wk after the training program was completed. Exercise-induced changes on airway cells and markers of airway inflammation were also assessed by sputum induction and venous blood samples. Mean power output during the 1,000 m test was 169 + or - 49 W/stroke at baseline, 174 + or - 49 W/stroke at 5 wk, and 200 + or - 60 W/stroke at 10 wk of training (P < 0.05). The median Mch dose used at baseline was 50 mg/ml (range 25-75 mg/ml) and remained constant per study design. At the pretraining evaluation, the percent reduction in the primary outcome, the inspiratory vital capacity (IVC) after inhalation of Mch in the absence of DIs was 31 +/- 13%; at week 5, the Mch-induced reduction in IVC was 22 + or - 19%, P = 0.01, and it further decreased to 15 + or - 11% at week 10 (P = 0.0008). The percent fall in IVC 4-6 wk after the end of training was 15 + or - 11% (P = 0.87 vs. end of training). Changes in airway cells were not associated with changes in airway responsiveness. Our data show that a course of exercise training can attenuate airway responsiveness against Mch inhaled in the absence of DIs in healthy subjects and suggest that a sedentary lifestyle may favor development of airways hyperresponsiveness.

Bronchial epithelial damage after a half-marathon in nonasthmatic amateur runners.

High neutrophil counts in induced sputum have been found in nonasthmatic amateur runners at rest and after a marathon, but the pathogenesis of airway neutrophilia in athletes is still poorly understood. Bronchial epithelial damage may occur during intense exercise, as suggested by investigations conducted in endurance-trained mice and competitive human athletes studied under resting conditions. To gain further information on airway changes acutely induced by exercise, airway cell composition, apoptosis, IL-8 concentration in induced sputum, and serum CC-16 level were measured in 15 male amateur runners at rest (baseline) and shortly after a half-marathon. Different from results obtained after a marathon, neutrophil absolute counts were unchanged, whereas bronchial epithelial cell absolute counts and their apoptosis increased significantly (P < 0.01). IL-8 in induced sputum supernatants almost doubled postrace compared with baseline (P < 0.01) and correlated positively with bronchial epithelial cell absolute counts (R(2) = 0.373, P < 0.01). Serum CC-16 significantly increased after all races (P < 0.01). These data show mild bronchial epithelial cell injury acutely induced by intense endurance exercise in humans, extending to large airways the data obtained in peripheral airways of endurance-trained mice. Therefore, neutrophil influx into the airways of athletes may be secondary to bronchial epithelial damage associated with intense exercise.

CD40 ligation protects bronchial epithelium against oxidant-induced caspase-independent cell death.

CD40 and its ligand regulate pleiotropic biological responses, including cell proliferation, differentiation, and apoptosis. In many inflammatory lung diseases, tissue damage by environmental or endogenous oxidants plays a major role in disease pathogenesis. As the epithelial barrier is a major target for these oxidants, we postulated that CD40, the expression of which is increased in asthma, plays a role in the regulation of apoptosis of bronchial epithelial cells exposed to oxidants. Using 16HBE 14o- cells exposed to oxidant stress, we found that ligation of CD40 (induced by G28-5 monoclonal antibodies) enhanced cell survival and increased the number of cells in G2/M (interphase between DNA synthesis and mitosis) of the cell cycle. This was associated with NF-kappaB and activator protein-1 activation and increased expression of the inhibitor of apoptosis, c-IAP1. However, oxidant stress-induced apoptosis was found to be caspase- and calpain-independent implicating CD40 ligation as a regulator of caspase-independent cell death. This was confirmed by the demonstration that CD40 ligation prevented mitochondrial release and nuclear translocation of apoptosis inducing factor. In conclusion, we demonstrate a novel role for CD40 as a regulator of epithelial cell survival against oxidant stress. Furthermore, we have identified, for the first time, an endogenous inhibitory pathway of caspase-independent cell death.